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Java Exercises: Add all the digits of a given positive integer until the result has a single digit

Java Basic: Exercise-108 with Solution

Write a Java program to add all the digits of a given positive integer until the result has a single digit.

Pictorial Presentation:

Java Basic Exercises: Add all the digits of a given positive integer until the result has a single digit

Sample Solution:

Java Code:

import java.util.Scanner;
public class Example108 {
     public static void main(String[] arg) {	
        Scanner in = new Scanner(System.in);	
       System.out.print("Input a positive integer: ");
        int n = in.nextInt(); 
		if (n>0)
		{
           System.out.print("The single digit number is: "+(n == 0 ? 0 : (n % 9 == 0 ? 9 : n % 9)));
		}
		System.out.println("\n");  
    }
}

Sample Output:

Input a positive integer: 25                                           
The single digit number is: 7

Flowchart:

Flowchart: Java exercises: Add all the digits of a given positive integer until the result has a single digit

Java Code Editor:

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Next: Write a Java program to form a staircase shape of n coins where every k-th row must have exactly k coins.

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Java: Tips of the Day

initial:

Returns all the elements of an array except the last one. Use Arrays.copyOfRange() to return all except the last one

public static <T> T[] initial(T[] elements) {
    return Arrays.copyOfRange(elements, 0, elements.length - 1);
}

Ref: https://bit.ly/3zEKw9u